Brief Answer: Due to viral infection. Detailed Answer: Hello, Thanks for trusting us with your health concern. The symptoms that your son is having are likely to be due to a viral fever. It is common to have rash as one of the symptoms of a viral flu. In most of the viral infections the rash starts after the fever subsides, may spread to the whole body or peak for a couple of days and then gradually subside on its own in few days to a week. The rash might be associated with itching and may respond to antihistamine drugs like cetrizine or hydroxyzine. The other possibilities though unlikely in your son's case could be a drug reaction to any medicines taken or bacterial sepsis.These are usually more severe and require prompt treatment. In your child they are not likely as he has no associated symptoms now. But if there is any new symptom like bleeding, pain, pus discharge, breathing difficulty then please consult your pediatrician for confirmation of diagnosis . If the present symptoms persist for more than a week from now please visit your doctor again to rule out bacterial infection. Please feel free to discuss further. I will be glad to answer the follow up queries that you have. Wishing you good health. Regards. Dr. Rakhi Tayal. For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Rakhi-Tayal

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